motor mount question
Thread Starter
Burning Brakes
Joined: Mar 2008
Posts: 838
Likes: 0
From: starting to wonder if im welcome here texas
motor mount question
i have a 454 going into a 81 vette and was wondering if 66 to 74 bb corvette motor mounts will fit in my 81 with no problems, they look different then the 1 1981 motor mount i have. transmission is a th-400 if it matters
thanks
thanks
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
The big block mounts should fit the frame fine once they are bolted to the engine.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Team Owner
Joined: Jul 2004
Posts: 40,422
Likes: 792
From: Redondo Beach, California
The frame motor mount horns for big blocks and small blocks are the same.
The motor mounts for big blocks and small blocks are the same.
...............
The confusion is that chevy engines during the 60's, 70's, 80's used two types of motor mounts, they differed primarily in that one was for wide frame horns and one was for narrower frame horns. I forget what classification our C3 frame horn widths are, I think they are the wider widths. Anyhow, C3 engine motor mounts are interchangeable for big blocks and small blocks.
The motor mounts for big blocks and small blocks are the same.
...............
The confusion is that chevy engines during the 60's, 70's, 80's used two types of motor mounts, they differed primarily in that one was for wide frame horns and one was for narrower frame horns. I forget what classification our C3 frame horn widths are, I think they are the wider widths. Anyhow, C3 engine motor mounts are interchangeable for big blocks and small blocks.
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Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
The frame motor mount horns for big blocks and small blocks are the same.
The motor mounts for big blocks and small blocks are the same.
...............
The confusion is that chevy engines during the 60's, 70's, 80's used two types of motor mounts, they differed primarily in that one was for wide frame horns and one was for narrower frame horns. I forget what classification our C3 frame horn widths are, I think they are the wider widths. Anyhow, C3 engine motor mounts are interchangeable for big blocks and small blocks.
The motor mounts for big blocks and small blocks are the same.
...............
The confusion is that chevy engines during the 60's, 70's, 80's used two types of motor mounts, they differed primarily in that one was for wide frame horns and one was for narrower frame horns. I forget what classification our C3 frame horn widths are, I think they are the wider widths. Anyhow, C3 engine motor mounts are interchangeable for big blocks and small blocks.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
You're probably right. This would make sense when trying to lower the engine in the bay a bit.
Instructor
Joined: Aug 2004
Posts: 174
Likes: 0
From: Roskilde
Actually when it comes to width at least 3 different motor mount exist, narrow for passanger cars, wide for corvette and even wider for truck?, just learned the hard way a c3 with too wide motor mounts can "hide" a misaligned crossmember 
Burning Brakes
Joined: Dec 2007
Posts: 952
Likes: 0
The frame motor mount horns for big blocks and small blocks are the same.
The motor mounts for big blocks and small blocks are the same.
...............
The confusion is that chevy engines during the 60's, 70's, 80's used two types of motor mounts, they differed primarily in that one was for wide frame horns and one was for narrower frame horns. I forget what classification our C3 frame horn widths are, I think they are the wider widths. Anyhow, C3 engine motor mounts are interchangeable for big blocks and small blocks.
The motor mounts for big blocks and small blocks are the same.
...............
The confusion is that chevy engines during the 60's, 70's, 80's used two types of motor mounts, they differed primarily in that one was for wide frame horns and one was for narrower frame horns. I forget what classification our C3 frame horn widths are, I think they are the wider widths. Anyhow, C3 engine motor mounts are interchangeable for big blocks and small blocks.
